I have never heard of the finish on brass knobs or pulls wearing off. I have brass throughout my house and they've all been fine. To answer your question, you can absolutely mix finishes throughout your house. Your thought to mix in brass with black will work well. I prefer to match my kitchen cabinet hardware to the sink faucet, but that's just MY preference. Love your Fantasy Brown, the slab is beautiful! When we first started designing our kitchen, we were eyeing that up, but ultimately decided on something else. Your kitchen will be gorgeous!

Both the Champagne Bronze Delta faucets and the Brizo stainless steel faucets we bought were above the cost of what you could get a standard faucet for in stainless steel with a traditional design. However, we were able to maximize discounts by shopping online for the lowest prices which sometimes involve a percentage off discount sale since Delta/Brizo and other brands put a cap on how low resellers can advertise the list prices. Also be aware that some faucets being ordered online right now are being delayed weeks out due to lower capacities in manufacturing and shipping delays due to the pandemic. Our faucet order placed last week is projected to arrive in 3 weeks. If cost is a big concern, maybe the polished nickel might be a compromise after all, but again, polished nickel is frequently higher in cost than stainless steel, so if it was the gold/brass color you really wanted, then polished nickel is only getting you halfway to that goal for an increased cost anyway.

To msrmom: I am attaching my other bathroom that is not quite 100% complete yet. Still have art to go.. But in this one we went with Brushed Nickel right down to the toilet flush handle. My vanity lights and the hanging light are white linen. both with brushed nickel. I feel like I am really stuck now on the black and white bathroom. I was reading that the gold could go out of style and the black, but I have had the hole cut into the counter so it's too late. I absolutely love the brushed nickel. It is a beautiful colour. What I could do is change the hardware to brushed nickel, toilet flusher and then maybe some pictures like the attached. This is not my favourite for art, but it got me thinking about silver type finish.

My first thought is also brushed nickel. Dark colors against white really call attention to themselves and that's not what I would be looking for in a cabinet pull. However, as long as you have definitely decided on a pull style, if it comes in multiple finishes buy a half dozen in a couple to try (as long as they're returnable). You just want to be sure when the holes are drilled that they're going to be right for whichever pull you choose. Knobs are straightforward but there are a lot of different pull sizes.